Magnetism and Spin Structures of Polymorphic 2D TMDs

Magnetism in two dimensions has, in the last few years, become an important research topic for both fundamental physics and technological advances. The discoveries of long-range ferromagnetic order in atomically thin CrI 3 and Cr 2 Ge 2 Te 6 in 2017 have sparked intense activity in exploring two-dimensional (2D) magnetic materials. This chapter mainly focuses on the magnetism and spin structures of polymorphic 2D TMDs. We first introduce the extensively explored 2D Cr-based magnetic materials and then present a brief overview of the recent experimental progress on other 2D magnetic TMDs. Various approaches for fabricating few-layer or monolayer magnetic materials, together with the characterization of their magnetic properties are systematically surveyed. The modulation of magnetic properties and relevant device applications are discussed, concluding with our perspectives on the existing challenges and opportunities in this field.